Viessmann Combi randomly fires-up

[Deleted User]

I had a Viessmann combi boiler installed last year. When the CH is off and I'm not running any hot water, every 20 or 30 minutes it will fire up for 10 or so seconds before quieting down again.

Is this some sort of preheat feature? Just that it doesn't mention anything about how often the boiler will fire up in the manual or if at all.

It uses enough gas everytime it does this to move the last red digit on the gas meter 3-4 numbers. Also I still need to run the tap before I get hot water.

C_Mababejive

http://www.viessmann.co.uk/content/dam/internet_uk/wb1c/wb1c_operating_.pdf

page 12

Viessmann confusingly call it a comfort function..

nickcc

Just for info. I also have the same model boiler fitted just over three years ago, unfortunately it stopped igniting just over the three years guarantee period so I had to call Viessmann for assistance.
The first person I spoke to told me they would arrange for an engineer to call but it would be at my cost, the next person I spoke to advised me that all Viessmann boilers from 2012 have a five year guarantee, the repair was carried out FOC the next day, turned out to be a faulty gas supply valve and control panel.

[Deleted User]

C_Mababejive wrote: »

http://www.viessmann.co.uk/content/dam/internet_uk/wb1c/wb1c_operating_.pdf

page 12

Viessmann confusingly call it a comfort function..

I did what it says on page 12 of that PDF but nothing happened. Although my boiler is a Vitodens 100 W, the LCD display is different to the one in the PDF manual. It doesn't have the outline of a house, all it displays is the temperature and little icons if the water or CH is on. Doesn't even have the space for the other things on the LCD panel.

All a mystery.